Hi james - What financial requirement category did you apply under ?
As Joebloggs has stated it is a little odd as you are sponsoring your wife ? don't quite understand why they would wish to understand her financial situation at all, especially at this stage of the process when you have not yet even submitted your complete documentation.
I am sure all is good though and there is no need to be concerned.
Terpe is the expert on these matters from my experience and I am sure will comment soon...